Develop Reference

Android: Uploading image without losing Exif data

In our app users have been uploading millions of images for years using (roughly) this code:
BitmapFactory.Options bmOptions = new BitmapFactory.Options();
bmOptions.inJustDecodeBounds = true;
BitmapFactory.decodeFile(postFilePath, bmOptions);
Bitmap roughBitmap = BitmapFactory.decodeFile(postFilePath, bmOptions);
ByteArrayOutputStream stream = new ByteArrayOutputStream();
roughBitmap.compress(Bitmap.CompressFormat.JPEG, 70, stream);
InputStream fis = new ByteArrayInputStream(stream.toByteArray());
int fileSize = stream.toByteArray().length;
conn.setRequestProperty("Content-Length", Integer.toString(fileSize));
conn.setFixedLengthStreamingMode(fileSize);
...
if (fis != null) {
byte[] buf = new byte[10240];
int read;
while ((read = fis.read(buf)) > 0) {
os.write(buf, 0, read);
totalBytesRead += read;
if (uploadProgressListener != null) {
try {
uploadProgressListener.onBytesUploaded(read);
} catch (Exception e) {
Log.e(e);
}
}
}
fis.close();
}
Recently we saw the need to preserve the Exif data of uploaded images. The problem is that the image Exif data is lost when compressing the bitmap. I thought of using ExifInterface for extracting this data from the original file:
ExifInterface oldExif = new ExifInterface(postFilePath);
String value = oldExif.getAttribute(ExifInterface.TAG_DATETIME);
..and then adding it to the InputStream fis and then continue uploading the file. The problem is that ExifInterface cannot save Exif data to an InputStream.
How can Exif data be retained in the images when they'er uploaded to the server?
It's not a duplicate:
Just to clarify deeper, I've tried using the suggested duplicate question by using this method:
public static void copyExif(String originalPath, InputStream newStream) throws IOException {
String[] attributes = new String[]
{
ExifInterface.TAG_DATETIME,
ExifInterface.TAG_DATETIME_DIGITIZED,
ExifInterface.TAG_EXPOSURE_TIME,
ExifInterface.TAG_FLASH,
ExifInterface.TAG_FOCAL_LENGTH,
ExifInterface.TAG_GPS_ALTITUDE,
ExifInterface.TAG_GPS_ALTITUDE_REF,
ExifInterface.TAG_GPS_DATESTAMP,
ExifInterface.TAG_GPS_LATITUDE,
ExifInterface.TAG_GPS_LATITUDE_REF,
ExifInterface.TAG_GPS_LONGITUDE,
ExifInterface.TAG_GPS_LONGITUDE_REF,
ExifInterface.TAG_GPS_PROCESSING_METHOD,
ExifInterface.TAG_GPS_TIMESTAMP,
ExifInterface.TAG_MAKE,
ExifInterface.TAG_MODEL,
ExifInterface.TAG_ORIENTATION,
ExifInterface.TAG_SUBSEC_TIME,
ExifInterface.TAG_WHITE_BALANCE
};
ExifInterface oldExif = new ExifInterface(originalPath);
ExifInterface newExif = new ExifInterface(newStream);
if (attributes.length > 0) {
for (int i = 0; i < attributes.length; i++) {
String value = oldExif.getAttribute(attributes[i]);
if (value != null)
newExif.setAttribute(attributes[i], value);
}
newExif.saveAttributes();
}
}
.. but got the exception java.io.IOException: ExifInterface does not support saving attributes for the current input. after newExif.saveAttributes(); because I'm trying to save the attributes to an InputStream. How else can I do it?

My solution:
As #amuttsch and #CommonsWare suggested, I:
saved the scaled/compressed bitmap to a temp file
copied the exif from the original file to the temp file
converted the temp file to a byte array and sent it to upload
.. then I found out that the server strips the Exif again while generating image variants :-P but that's another story which server guys are now working to correct.
Main code:
...
// Copy original Exif to scaledBitmap
String tempFilePath = getTempFilePath(postFilePath);
try {
FileOutputStream out = new FileOutputStream(tempFilePath);
scaledBitmap.compress(Bitmap.CompressFormat.JPEG, 70, out);
copyExif(postFilePath, tempFilePath);
} catch (Exception e) {
e.printStackTrace();
}
// Get stream from temp (exif loaded) file
File tempFile = new File(tempFilePath);
byte[] byteFile = readFile(tempFile);
fis = new ByteArrayInputStream(byteFile);
// Remove the temp file
boolean deleted = tempFile.delete();
// Finalize
int fileSize = byteFile.length;
conn.setRequestProperty("Content-Length", Integer.toString(fileSize));
conn.setFixedLengthStreamingMode(fileSize);
...
getTempFilePath():
private String getTempFilePath(String filename) {
String temp = "_temp";
int dot = filename.lastIndexOf(".");
String ext = filename.substring(dot + 1);
if (dot == -1 || !ext.matches("\\w+")) {
filename += temp;
} else {
filename = filename.substring(0, dot) + temp + "." + ext;
}
return filename;
}
copyExif():
public static void copyExif(String originalPath, String newPath) throws IOException {
String[] attributes = new String[]
{
ExifInterface.TAG_DATETIME,
ExifInterface.TAG_DATETIME_DIGITIZED,
ExifInterface.TAG_EXPOSURE_TIME,
ExifInterface.TAG_FLASH,
ExifInterface.TAG_FOCAL_LENGTH,
ExifInterface.TAG_GPS_ALTITUDE,
ExifInterface.TAG_GPS_ALTITUDE_REF,
ExifInterface.TAG_GPS_DATESTAMP,
ExifInterface.TAG_GPS_LATITUDE,
ExifInterface.TAG_GPS_LATITUDE_REF,
ExifInterface.TAG_GPS_LONGITUDE,
ExifInterface.TAG_GPS_LONGITUDE_REF,
ExifInterface.TAG_GPS_PROCESSING_METHOD,
ExifInterface.TAG_GPS_TIMESTAMP,
ExifInterface.TAG_MAKE,
ExifInterface.TAG_MODEL,
ExifInterface.TAG_ORIENTATION,
ExifInterface.TAG_SUBSEC_TIME,
ExifInterface.TAG_WHITE_BALANCE
};
ExifInterface oldExif = new ExifInterface(originalPath);
ExifInterface newExif = new ExifInterface(newPath);
if (attributes.length > 0) {
for (int i = 0; i < attributes.length; i++) {
String value = oldExif.getAttribute(attributes[i]);
if (value != null)
newExif.setAttribute(attributes[i], value);
}
newExif.saveAttributes();
}
}
readFile():
public static byte[] readFile(File file) throws IOException {
// Open file
RandomAccessFile f = new RandomAccessFile(file, "r");
try {
// Get and check length
long longlength = f.length();
int length = (int) longlength;
if (length != longlength)
throw new IOException("File size >= 2 GB");
// Read file and return data
byte[] data = new byte[length];
f.readFully(data);
return data;
} finally {
f.close();
}
}

The problem is that the image Exif data is lost when compressing the bitmap
The EXIF data is lost when reading in the Bitmap. A Bitmap has no EXIF tags.
How can Exif data be retained in the images when they'er uploaded to the server?
Stop reading in the Bitmap. Just upload the contents of postFilePath as-is. It will contain whatever EXIF tags it contains.
My assumption is that you are reading in the Bitmap in the hope that saving it again in 70% JPEG quality will result in meaningful bandwidth savings. I suspect that you are not saving very much, and you may be increasing the bandwidth in some cases (e.g., postFilePath points to a PNG). Your costs are a chunk of CPU time, an increased risk of an OutOfMemoryError, and the loss of your EXIF tags.
If, instead, the convert-to-70%-JPEG is some sort of data normalization approach, do that work on the server, where you have more CPU power, more disk space, more RAM, and continuous power.

Source: https://stackoverflow.com/a/11572752/8252521
Answered by: https://stackoverflow.com/users/1592398/code-jaff
Convert the file to bitmap by
Bitmap bi = BitmapFactory.decode(filepath + "DSC00021.jpg");
You can specify options too, look at API documentation
Or if you want to exchange the meta data from one file to another,
sanselan will probably be the best choice. This would be much
helpful when you manipulating the image, for example re-size.
The sample code will guide you in a right direction.

You need to just create a new OutputStream to preserve the Exif Information. There is no need of creating a new File.

mp3 not saving to sd correctly; how to save mp3 to sd card?

I've been looking at this site for the past 3 or so hours. How to copy files from 'assets' folder to sdcard?
This is the best I could come up with because I'm only trying to copy one file at a time.
InputStream in = null;
OutputStream out = null;
public void copyAssets() {
try {
in = getAssets().open("aabbccdd.mp3");
File outFile = new File(root.getAbsolutePath() + "/testf0lder");
out = new FileOutputStream(outFile);
copyFile(in, out);
in.close();
in = null;
out.flush();
out.close();
out = null;
} catch (IOException e) {
Log.e("tag", "Failed to copy asset file: ", e);
}
}
private void copyFile(InputStream in, OutputStream out) throws IOException {
byte[] buffer = new byte[1024];
int read;
while ((read = in.read(buffer)) != -1) {
out.write(buffer, 0, read);
}
}
I've figured out how to create a file and save a text file. http://eagle.phys.utk.edu/guidry/android/writeSD.html
I would rather save an mp3 file to the sdcard rather than a text file.
When I use this code I provided, I get a text document that same size as the aabbccdd.mp3 file. It does not create a folder and save an .mp3 file. It saves a text document in the root folder. When you open it, I see a whole bunch of chinese letters, but at the top in English I can see the words WireTap. WireTap Pro was the program I used to record the sound so I know the .mp3 is passing through. It's just not creating a folder and then saving a file like the above .edu example.
What should I do?

I think you should do something like that -[Note: this i used for some other formats not mp3 but its works on my app for multiple format so i hope it will work for u too.]
InputStream in = this.getAssets().open("tmp.mp3"); //give path as per ur app
byte[] data = getByteData(in);
Make sure u have the folder already exists on path, if folder is not there it will not save content correctly.
byteArrayToFile(data , "testfolder/tmp.mp3"); //as per ur sdcard path, modify it.
Now the methods ::
1) getByteData from inputstream -
private byte[] getByteData(InputStream is)
{
byte[] buffer= new byte[1024]; /* or some other number */
int numRead;
ByteArrayOutputStream bytes = new ByteArrayOutputStream();
try{
while((numRead = is.read(buffer)) > 0) {
bytes.write(buffer, 0, numRead);
}
return bytes.toByteArray();
}
catch(Exception e)
{ e.printStackTrace(); }
return new byte[0];
}
2) byteArrayToFile
public void byteArrayToFile(byte[] byteArray, String outFilePath){
FileOutputStream fos;
try {
fos = new FileOutputStream(outFilePath);
fos.write(byteArray);
fos.close();
} catch (Exception e) {
e.printStackTrace();
}
}

How to display the JPEG Image directly from byte array (Before saving Image)?

I am receiving a jpeg image (Image size: 50KB) from client socket and saving in emulator SD Card. From there I am displaying the jpg image in Imageview. But I want to display the image before saving image on the SD Card because our android appli will receive the continous images from sockets, If I follow receive, save and display method then it will become very slow process, so to increase the speed I want display from ram only. For this I need to save the image array temporarily on the RAM. From there I planed to display and save by using the separate threads. So please guide me how to display the image from byte array.
Note: I am receiving JPEG image from socket, not .bmp or .gif or .png.
Below is my code for receiving the image from tcp socket. (Its working fine)
(Note: This is done in seperate thread, don't try it in UI thread.)
public byte[] mybytearray = new byte[310000];
private int bytesRead=0;
private int current = 0;
ServerSocket serverSocket = new ServerSocket(SERVERPORT);
Socket client = serverSocket.accept();
try {
myDir=new File("/mnt/sdcard/saved_images");
if (!myDir.exists()){
myDir.mkdir();
}else{
Log.d("ServerActivity","Folder Already created" );
}
String fpath = "/image0001.jpg";
File file = new File (myDir, fpath);
if (file.exists ()) file.delete ();
InputStream is = client.getInputStream();
FileOutputStream fos = new FileOutputStream(file);
BufferedOutputStream bos = new BufferedOutputStream(fos);
bytesRead = is.read(mybytearray,0,mybytearray.length);
current = bytesRead;
do {
bytesRead = is.read(mybytearray, current, (mybytearray.length-current));
if(bytesRead >= 0) current += bytesRead;
} while(bytesRead > -1);
bos.write(mybytearray, 0 , current);
Log.d("ServerActivity","Reconstructing Image from array");
bos.flush();
bos.close();
fos.flush();
fos.close();
is.close();
client.close();
serverSocket.close();
} catch (Exception e) {
e.printStackTrace();
}

Try inserting this code snippet into your code:
do {
bytesRead = is.read(mybytearray, current, (mybytearray.length-current));
if(bytesRead >= 0) current += bytesRead;
} while(bytesRead > -1);
ByteArrayInputStream inputStream = new ByteArrayInputStream(myByteArray);
bitmap = BitmapFactory.decodeStream(inputStream);
ImageView picture = new ImageView(this);
picture.setImageBitmap(bitmap);
bos.write(mybytearray, 0 , current);

Use Bitmap, create it from Byte Array,
Bitmap bitmap;
bitmap= BitmapFactory.decodeByteArray(mybytearray, 0, mybytearray.length);

Convert byte[] to bitmap.
Try the following
ByteArrayInputStream imageStream = new ByteArrayInputStream(byte[] array);
Bitmap bitmap = BitmapFactory.decodeStream(imageStream);

Does not read the entire input stream in android

I am trying to read a response from a server and transform it from InputStream to String but something goes wrong and i cannot see right now why.
InputStream is = entity.getContent();
FileOutputStream folder = new FileOutputStream(
Environment.getExternalStorageDirectory()
+ "/test.xml");
try {
byte[] buf = new byte[1048576];
int current = 0;
int newCurrent = 0;
while ((current = is.read(buf)) != -1) {
newCurrent = newCurrent + current;
folder.write(buf, 0, current);
}
System.out.println("returned folder" + folder);
folder.flush();
} catch (IOException e) {
System.out.println("error on reading input: " + e.getMessage());
}
This is the error:
error on reading input: Socket closed
This is the error I get and another problem that i don't understand is why it does not read the entire content from InputStream(maybe because it's all in one line?).
Thanks.

you dont need to read entire stream in one shot and put it in a byte array, in fact you read it in parts through while loop and put the contents in file stream gradually:
int count;
byte[] filebytes = new byte[1024];
while((count = is.read(filebytes)) != -1){
folder.write(filebytes, 0, count); //writing buffer into file
}
in.close();
folder.flush();
folder.close();

According to stacktrace your crash happens in readLine() while your code uses is.read(buf).
DO these match together?

Android: How to download a .png file using Async and set it to ImageView?

I've got the URL of a .png image, that needs to be downloaded and set as a source of an ImageView. I'm a beginner so far, so there are a few things I don't understand:
1) Where do I store the file?
2) How do I set it to the ImageView in java code?
3) How to correctly override the AsyncTask methods?
Thanks in advance, will highly appreciate any kind of help.

I'm not sure you can explicity build a png from a download. However, here is what I use to download images and display them into Imageviews :
First, you download the image :
protected static byte[] imageByter(Context ctx, String strurl) {
try {
URL url = new URL(urlContactIcon + strurl);
InputStream is = (InputStream) url.getContent();
byte[] buffer = new byte[8192];
int bytesRead;
ByteArrayOutputStream output = new ByteArrayOutputStream();
while ((bytesRead = is.read(buffer)) != -1) {
output.write(buffer, 0, bytesRead);
}
return output.toByteArray();
} catch (MalformedURLException e) {
e.printStackTrace();
return null;
} catch (IOException e) {
e.printStackTrace();
return null;
}
}
And then, create a BitMap and associate it to the Imageview :
bytes = imagebyter(this, mUrl);
bm = BitmapFactory.decodeByteArray(bytes, 0, bytes.length);
yourImageview.setImageBitmap(bm);
And that's it.
EDIT
Actually, you can save the file by doing this :
File file = new File(fileName);
FileOutputStream fos = new FileOutputStream(file);
fos.write(imagebyter(this, mUrl));
fos.close();

You can explicity build a png from a download.
bm.compress(Bitmap.CompressFormat.PNG, 100, out);
100 is your compression (PNG's are generally lossless so 100%)
out is your FileOutputStream to the file you want to save the png to.